The present invention relates to an improved sheet inverting system, and more particularly to an inverter providing improved handling of variable sized sheets within the inverter which employs a slow speed drive mode for improved reliability.
As xerographic and other copiers/printers increase in speed, and become more automatic, it is increasingly important to provide higher speed yet more reliable and more automatic handling of both the copy sheets being made by the copier and the original document sheets being copied. It is desired to accommodate sheets which may vary widely in size, weight, thickness, material, condition, humidity, age, etc. These variations change the beam strength or flexural resistance and other characteristics of the sheets. Yet the desire for automatic and high speed handling of such sheets without jams, misfeeds, uneven feeding times, or other interruptions increases the need for reliability of all sheet handling components. A sheet inverter is one such sheet handling component with particular reliability problems.
Although, a sheet inverter is referred to in the copier art as an xe2x80x9cinverterxe2x80x9d, its function is not necessary to immediately turn the sheet over (i.e., exchange one face for the other). Its function is to effectively reverse the sheet orientation in its direction of motion. That is, to reverse the lead edge and trail edge orientation of the sheet. Typically in inverter devices, as disclosed here, the sheet is driven or fed by feed rollers or other suitable sheet driving mechanisms into a sheet reversing chute. By reversing the motion of the sheet within the chute and feeding it back out from the chute, the desired reversal of the leading and trailing edges of the sheet in the sheet path is accomplished. Depending on the location and orientation of the inverter in a particular sheet path, this may, or may not, also accomplish the inversion (turning over) of the sheet. In some applications, for example, where the xe2x80x9cinverterxe2x80x9d is located at the corner of a 90xc2x0 to 180xc2x0 inherent bend in the copy sheet path, the inverter may be used to actually prevent inverting of a sheet at that point, i.e., to maintain the same side of the sheet face-up before and after this bend in the sheet path. On the other hand, if the entering and departing path of the sheet, to and from the inverter, is in substantially the same plane, the sheet will be inverted by the inverter. Thus, inverters have numerous applications in the handling of either original documents or copy sheets to either maintain, or change, the sheet orientation.
Without the invention, the sheet can move on the trail edge due to the fast speed of air movement. The sheet trail edge can fly towards the wrong position if paper movement is too fast. This could cause a jam into deflector 300.